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thuyque2009
2 năm trước
Một thỏi kim loại đặc màu vàng có m = 350g, V = 20 cm3. Biết khối lượng riêng của vàng D1 =19,3g/cm3, của bạc D2 = 10,5g/cm3. a. Chứng minh rằng đó không phải là thỏi vàng nguyên chất b. Biết thỏi kim loại đó gồm vàng và bạc. Tính khối lượng vàng có trong thỏi hợp kim đó ? HELPPPP!!!!
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